1. Field of the Invention
The field of the invention relates generally to thermally insulated refrigeration appliance structures, and more particularly to refrigeration appliance structures having a five-sided, box-like vacuum panel.
2. Description of Related Art
It is usual to insulate some appliances from the surrounding environment. For example, in a refrigerator, freezer, oven/range or dishwasher, an internal compartment of the appliance is typically insulated to minimize thermal heat transfer between the compartment and the surrounding environment. The particular type of insulation utilized can actually vary. In refrigerators, for example, it is known to inject a foam insulation into a cavity formed between an outer case of the refrigerator and a liner that defines one or more internal food storage compartments. Once the foamed insulation cures, a solid insulation barrier is provided which not only thermally insulates each internal compartment but also adds structural integrity to the overall cabinet assembly.
Another type of thermal insulation that has been used in appliances and other cabinet structures are insulation panels. In general, such panels are pre-formed into desired shapes and, in the case of a refrigerator, positioned between inner walls of the outer case and the liner. Typically, each panel is defined by first and second liner sheets which are sealed together about their edges and between which is arranged a low thermal conductive insulation material, for example, fiberglass. To increase thermal insulation properties, the interiors of such panels can be evacuated prior to insertion of the panels into the case. The case and the vacuum panels are constructed separately and then assembled to form the overall appliance structure.
The use of vacuum panels can enhance the thermal insulation properties of cabinet structures over foam insulation. However, known vacuum panels typically do not extend into the corners of the cabinet which create areas that cause temperature gradients and heat leaking through the insulation chamber of the appliance.